Arctic Ocean meltdown: Say goodbye to the Arctic ice cap

The Arctic ice cap will disappear? A new study says the Arctic Ocean could be ice-free during the summer months in less than 20 years.

Reuters

A US Coast Guard C-130 flies over broken sea ice in the Beaufort Sea. Scientists say they expect the Arctic Ocean to be ice free in the summer within the next few decades. Much of that melt-back may come within the next decade, some researchers say.

The new data "supports the consensus view -- based on seasonal variation of ice extent and thickness, changes in temperature, winds, and especially ice composition -- that the Arctic will be ice-free in the summer within about 20 years." By "composition" he's referring to the ratio of thick multi-year ice that resists summer melt to become the foundation for the next winter's freeze and thinner one- or two-year-old ice that fails to make it through the following summer.

This year's summer ice reached the third lowest extent since scientists began tracking the ice with satellites in 1979. But more first-year and second year ice has survived compared with the past couple of summer, notes Walt Meier, a senior scientist at the center.

"If this ice remains in the Arctic through the winter, it will thicken, which gives some hope of stabilizing the ice cover over the next few years," he said in a statement. "However, the ice is still much younger and thinner than it was in the 1980s, leaving it vulnerable to melt during the summer.”

The center's director, Mark Serreze, added that “it’s nice to see a little recovery over the past couple years, but there’s no reason to think that we’re headed back to conditions seen back in the 1970s. We still expect to see ice-free summers sometime in the next few decades.”

So where do the latest data leave the matter? Scientists always relish more data. And it's useful to try to provide ground truth to information satellites gather. But the Catlin-WWF results don't alter the picture the wider group of polar scientist has been assembling. Global warming continues to take its toll on Arctic sea ice. But natural variability, which plants itself atop the longer-term temperature trends, make precise predictions of an ice-free summer at the top of the world difficult. Hence the "sometime."